Propuesta de modelo de evaluación multidimensional de los aprendizajes en ciencias naturales y su relación con la estructura de la didáctica de las ciencias

La propuesta de modelo evaluativo multidimensional en Ciencias Naturales que se presenta, tiene como soporte la consideración de la evaluación como uno de los campos de estudio de las Didáctica de las Ciencias; y comprender que esta última es coherente con las dinámicas de las mismas Ciencias Naturales, significa una especificidad epistemológica, la que a su vez exige especificidad para la Evaluación en el mismo campo de la enseñanza. Desde esta perspectiva se presenta la Evaluación en Ciencias desde varias dimensiones: conceptual, administrativa-metodológica, actitudinal, comunicativa, e histórico-epistemológica; quedando como expectativa un mayor reconocimiento de los contextos de los grupos y naciones.Palabras clave: didáctica de las ciencias; evaluación en ciencias; ciencias naturales.Proposal of multidimensional evaluation model of the learning in the natural sciences and their relationship with the structure of the sciences educationThe proposal of multidimensional evaluation model in Natural Sciences that is presented, it has support on the consideration of the evaluation like one of the fields of study in the Sciences Education; and to understand that this last one is coherent with the Natural Sciences dynamics, it means a epistemological specificity, and it demands specificity for the Evaluation in the same field of the teaching. From this perspective the Evaluation in Sciences is presented in several dimensions: conceptual, administrative-methodological, of the attitudes, of the communication, and historical-epistemological; remaining as expectation a bigger recognition of the contexts of the groups and nations.Keywords: sciences education; sciences evaluation; natural sciences

Enhancing resistance against African weevils through development of transgenic sweetpotato cultivars (Ipomoea batatas (L.) Lam.) expressing cry7Aa1, cry3Ca1 and ET33-34 genes.

Sweetpotato (Ipomoea batatas) is one of the most important food crops in tropical and subtropical countries. In Sub-Saharan Africa, sweetpotato is mainly produced for consumption and as a source of income by resource-poor farmers. However, their production is limited by severe damage caused by pests and diseases. The African weevils Cylas puncticollis and C. brunneus are the main biological constraints that may cause losses between 50 and 100%. Biotechnological approaches to control weevils include the introduction of genes encoding Cry proteins found to be active against these pests. To that end, several protocols for sweetpotato regeneration and transformation by organogenesis or somatic embryogenesis have been developed but their efficiency remains largely genotype-dependent and time-consuming. In this study, 31 African sweetpotato cultivars from CIP genebank were screened for regeneration and transformation efficiencies by organogenesis and somatic embryogenesis. Additionally, “Jewel” and “Jonathan” cultivars were used as organogenic and embryogenic controls, respectively. Regeneration by organogenesis was conducted using a two-step protocol including 2,4-D then thidiazuron, zeatin or kinetin while regeneration by embryogenesis was performed using a three-step protocol, each one using a different hormone (2,4,5-T, ABA and AG3). Higher than 40% regeneration efficiencies were obtained for 8 cultivars (Jewel, Imby, Kawogo, Luapula, Mafutha, CIP440163, Zambezi and Ukerewe) with an organogenesis protocol and 8 cultivars (Jonathan, Imby, K51/3251, Bwanjule, CIP440163, SPK004, New Kawogo and KSP 11) with an embryogenesis protocol. Genetic transformation of sweetpotato with Jewel by organogenesis and Imby, CIP440163 and Jonathan by somatic embryogenesis has been achieved using chimerical genes coding for three of the most active proteins (Cry7Aa1, ET33-34, and Cry3Ca1) against African weevils. Transgenic events have been confirmed by kanamycin resistant calli test, PCR and Southern blot. Transcriptional activity and Cry protein accumulation are being tested in leaves and storage roots by Real time PCR and DAS-ELISA respectively

Dipolar origin of the gas-liquid coexistence of the hard-core 1:1 electrolyte model

We present a systematic study of the effect of the ion pairing on the gas-liquid phase transition of hard-core 1:1 electrolyte models. We study a class of dipolar dimer models that depend on a parameter R_c, the maximum separation between the ions that compose the dimer. This parameter can vary from sigma_{+/-} that corresponds to the tightly tethered dipolar dimer model, to R_c --> infinity, that corresponds to the Stillinger-Lovett description of the free ion system. The coexistence curve and critical point parameters are obtained as a function of R_c by grand canonical Monte Carlo techniques. Our results show that this dependence is smooth but non-monotonic and converges asymptotically towards the free ion case for relatively small values of R_c. This fact allows us to describe the gas-liquid transition in the free ion model as a transition between two dimerized fluid phases. The role of the unpaired ions can be considered as a perturbation of this picture.Comment: 16 pages, 13 figures, submitted to Physical Review

Clinical standards for drug-susceptible TB in children and adolescents

BACKGROUND: These clinical standards aim to provide guidance for diagnosis, treatment, and management of drug-susceptible TB in children and adolescents. METHODS: Fifty-two global experts in paediatric TB participated in a Delphi consensus process. After eight rounds of revisions, 51/52 (98%) participants endorsed the final document. RESULTS: Eight standards were identified: Standard 1, Age and developmental stage are critical considerations in the assessment and management of TB; Standard 2, Children and adolescents with symptoms and signs of TB disease should undergo prompt evaluation, and diagnosis and treatment initiation should not depend on microbiological confirmation; Standard 3, Treatment initiation is particularly urgent in children and adolescents with presumptive TB meningitis and disseminated (miliary) TB; Standard 4, Children and adolescents should be treated with an appropriate weight-based regimen; Standard 5, Treating TB infection (TBI) is important to prevent disease; Standard 6, Children and adolescents should receive home-based/community-based treatment support whenever possible; Standard 7, Children, adolescents, and their families should be provided age-appropriate support to optimise engagement in care and clinical outcomes; and Standard 8, Case reporting and contact tracing should be conducted for each child and adolescent. CONCLUSION: These consensus-based clinical standards, which should be adapted to local contexts, will improve the care of children and adolescents affected by TB.National Institutes of HealthRevisión por pare

Acceptability and feasibility of a virtual community of practice to primary care professionals regarding patient empowerment : A qualitative pilot study

Background: Virtual communities of practice (vCoPs) facilitate online learning via the exchange of experiences and knowledge between interested participants. Compared to other communities, vCoPs need to overcome technological structures and specific barriers. Our objective was to pilot the acceptability and feasibility of a vCoP aimed at improving the attitudes of primary care professionals to the empowerment of patients with chronic conditions. Methods: We used a qualitative approach based on 2 focus groups: one composed of 6 general practitioners and the other of 6 practice nurses. Discussion guidelines on the topics to be investigated were provided to the moderator. Sessions were audio-recorded and transcribed verbatim. Thematic analysis was performed using the ATLAS-ti software. Results: The available operating systems and browsers and the lack of suitable spaces and time were reported as the main difficulties with the vCoP. The vCoP was perceived to be a flexible learning mode that provided up-to-date resources applicable to routine practice and offered a space for the exchange of experiences and approaches. Conclusions: The results from this pilot study show that the vCoP was considered useful for learning how to empower patients. However, while vCoPs have the potential to facilitate learning and as shown create professional awareness regarding patient empowerment, attention needs to be paid to technological and access issues and the time demands on professionals. We collected relevant inputs to improve the features, content and educational methods to be included in further vCoP implementation. Trial registration: ClinicalTrials.gov, NCT02757781. Registered on 25 April 2016

Contourite depositional system after the exit of a strait: Case study from the late Miocene South Rifian Corridor, Morocco

Idealized facies of bottom current deposits (contourites) have been established for fine-grained contourite drifts in modern deep-marine sedimentary environments. Their equivalent facies in the ancient record however are only scarcely recognized due to the weathered nature of most fine-grained deposits in outcrop. Facies related to the erosional elements (i.e. contourite channels) of contourite depositional systems have not yet been properly established and related deposits in outcrop appear non-existent. To better understand the sedimentary facies and facies sequences of contourites, the upper Miocene contourite depositional systems of the South Rifian Corridor (Morocco) is investigated. This contourite depositional system formed by the dense palaeo-Mediterranean Outflow Water. Foraminifera assemblages were used for age-constraints (7.51 to 7.35 Ma) and to determine the continental slope depositional domains. Nine sedimentary facies have been recognized based on lithology, grain-size, sedimentary structures and biogenic structures. These facies were subsequently grouped into five facies associations related to the main interpreted depositional processes (hemipelagic settling, contour currents and gravity flows). The vertical sedimentary facies succession records the tectonically induced, southward migration of the contourite depositional systems and the intermittent behaviour of the palaeo-Mediterranean Outflow Water, which is mainly driven by precession and millennial-scale climate variations. Tides substantially modulated the palaeo-Mediterranean Outflow Water on a sub-annual scale. This work shows exceptional examples of muddy and sandy contourite deposits in outcrop by which a facies distribution model from the proximal continental slope, the contourite channel to its adjacent contourite drift, is proposed. This model serves as a reference for contourite recognition both in modern environments and the ancient record. Furthermore, by establishing the hydrodynamics of overflow behaviour a framework is provided that improves process-based interpretation of deep-water bottom current deposits